Epoxy Soundboard Repair- Coloring of Epoxy

[Andrew Olson]

This is a multi-part message in MIME format.

---------------------- multipart/alternative attachment
Wow, that picture is great!

That's really nice.  Thanks to everyone for your input.

Andrew Olson
  -----Original Message-----
  From: pianotech-bounces@ptg.org [mailto:pianotech-bounces@ptg.org]On
Behalf Of David V. Anderson
  Sent: Tuesday, April 12, 2005 10:50 AM
  To: pianotech@ptg.org
  Subject: RE: Epoxy Soundboard Repair- Coloring of Epoxy


  My formula recently has been the System Three epoxy colorant.  This is a
stiff, opaque paste, designed to work with epoxy resins.  Two cautions:  The
color slows the hardening time considerably, renders the epoxy less brittle,
and too much will prevent it from hardening altogether. (at least on a
non-geologic time scale).  Also, the color tends to weaken bond strength and
the epoxy's ability to flow and expel air.  I usually start with a batch of
clear epoxy to wet the crack and fill to the bottom.  I have used them with
West Systems resin and slow hardener, and I would assume they work fine with
System Three's own products.



  I have purchased the paste in yellow, brown, and most importantly, white.
I believe they also make red, which would probably be handy in tiny amounts
to "orange" up the mix.  Just adding the colors makes too deep a saturation
long before the desired level of opacity is reached, so start with white.
With a semi-translucent white base, much less of the deeper colors are
needed.  Experiment with how much, but less is definitely better.  I add the
smallest amount of paste necessary to do the job.  A batch that won't cure
would be a real disappointment, and I disclaim all responsibility for such
an outcome.



  Even with the color, this stuff will migrate.  I have come within an inch
or so of the end of a crack that diminished to zero width, and have had it
wick to the very end.  It does tend to trap air bubbles, so be careful
mixing and actively squeegee it in over its entire pot life.  Tapping the
board at intervals seems to help.



  The photo shows an unfinished board with two filled cracks.  As was
mentioned earlier, check color against a wet board for a closer match.
These did match quite well when finished.



  Like many others on the list, I'm not trying to make cracks disappear, or
pretend they never happened.  But they should still be pretty to look at
with all your plate work, shiny pins, and that expensive decal.  If making
them somewhat attractive really weren't an objective, we'd color them blue!





  David V. Anderson, RPT

  Waukesha, WI



---------------------- multipart/alternative attachment
An HTML attachment was scrubbed...
URL: https://www.moypiano.com/ptg/pianotech.php/attachments/50/a9/d7/f5/attachment.htm

---------------------- multipart/alternative attachment--